1. Field of the Invention
The present invention relates to an active filter, an image capture system, and an image capturing method, and in particular to an active filter, an image capture system, and an image capturing method, capable of actively switching between a visible light capture mode, an infrared light capture mode, and a visible light plus infrared light capture mode.
2. Description of the Related Art
Infrared light capture can be used in night vision, motion capture, material identification, and temperature difference identification, which differs from visible light capture. Under the requirements for taking a picture, infrared light capture can be utilized with an infrared flashlight in a dark environment to prevent the user from feeling dazzled because of a white light flashlight. In addition, when infrared light is utilized in visible light capture, the infrared light can used for assisting in focus, compensating for the image quality of visible light capture, enhancing image sharpness, or taking a special atmospheric photograph.
A conventional camera requires a filter to block or allow infrared light passing through. Therefore, when different capture modes are switched to meet different conditions, the filter should be changed. However, camera modules are requested for miniaturization (for example, the camera module of a mobile phone), so changing filters is not appropriate.
Therefore, an active filter or an image capture system is needed, which is capable of freely switching between a visible light capture mode, an infrared light capture mode, and a visible light plus infrared light capture mode.